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arXiv · 2106.15957

Temperature Dependence of Polymer Network Diffusion

Takeshi Fujiyabu·Takamasa Sakai·Ryota Kudo·Yuki Yoshikawa·Takuya Katashima·Ung-il Chung·Naoyuki Sakumichi
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Abstract

The swelling dynamics of polymer gels are characterized by the (collective) diffusion coefficient $D$ of the polymer network. Here, we measure the temperature dependence of $D$ of polymer gels with controlled homogeneous network structures using dynamic light scattering. An evaluation of the diffusion coefficient at the gelation point $D_{\mathrm{gel}}$ and the increase therein as the gelation proceeds $ΔD\equiv D-D_{\mathrm{gel}}$ indicates that $ΔD$ is a linear function of the absolute temperature with a significantly large negative constant term. This feature is formally identical to the recently discovered "negative energy elasticity" [Y. Yoshikawa et al., Phys. Rev. X 11, 011045 (2021) (arXiv:1912.13191)], demonstrating a nontrivial similarity between the statics and dynamics of polymer networks.

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Takeshi Fujiyabu, Takamasa Sakai, Ryota Kudo, Yuki Yoshikawa, Takuya Katashima, Ung-il Chung, Naoyuki Sakumichi. 2021-12-04. Temperature Dependence of Polymer Network Diffusion. https://doi.org/10.1103/physrevlett.127.237801

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